β-粉样和聚合物的清除取决于大小,并因炎症挑战而改变
Emre Fertan1,2, Christy Hung3,4, John S H Danial1,2
1Yusuf Hamied Department of Chemistry, University of Cambridge, Cambridge CB2 1EW, UK.
Brain communications
|January 3, 2025
概括
阿尔茨海默病的研究揭示了一个取决于大小的清除β-粉样和聚合物的机制. 这一发现揭示了炎症如何影响阿尔茨海默病中的聚合物形成和清除.
科学领域:
- 神经科学是一个神经科学.
- 细胞生物学 细胞生物学
- 阿尔茨海默氏症疾病研究研究
背景情况:
- 在阿尔茨海默病 (AD) 发病过程中,细胞外β-粉样蛋白聚合,炎症和高酸化蛋白聚合之间的相互作用是复杂的,并未完全理解.
- 之前的研究表明,免疫挑战,如瘤亡因子α (TNF-α),可以改变AD相关突变的神经元中的细胞外β片积聚物.
研究的目的:
- 在人类诱导多能干细胞 (hiPSC) 衍生皮质神经元中量化和描述细胞内和细胞外β-粉样蛋白和AT8阳性tau聚合物.
- 调查TNF-α对具有或没有 presenilin 1 (PS1) 突变的神经元中的聚合形成和清除的影响.
- 探索潜在的依赖大小的聚合清除机制及其对AD病原性的影响.
主要方法:
- 利用单分子检测和超分辨率成像技术来分析聚合物形态和分布.
- 在携带家族AD相关PS1突变的hiPSC衍生皮质神经元中比较聚合物形成和清除与同源对照.
- 研究了TNF-α治疗对细胞模型和ex vivo人类和小鼠大脑样本的总体特征的影响.
主要成果:
- PS1突变导致了先前存在的AD类病理,细胞内和细胞外β-粉样和细胞内聚合物增加.
- TNF-α治疗主要增加了PS1突变神经元中的细胞内β-粉胺聚合物,而同位素对照显示细胞外β-粉胺和细胞内/细胞外粉胺聚合物的增加,表明明显的炎症反应.
- 确定了一种依赖大小的聚合物清除机制,其中较小的聚合物被清除,而较大的聚合物保持细胞内,在神经元培养和ex vivo脑组织中一致.
结论:
- 提出了一种新的,取决于大小的机制,控制β-粉样蛋白和tau聚合物的清除,这可能解释了它们在AD中的差异性细胞内和细胞外定位.
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- 表明神经元细胞的清除较大的聚合物的能力有限,这有助于细胞内积累和细胞外β-粉样蛋白沉积.
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